Thing to do when clipping occurs:
- Use a limiter
- Don't necessarily turn down compression, but vary the gain levels and threshold. Adjust up or down as needed.
- Just turn down the volume.
- Cut out unnecessary frequencies by EQing the individual tracks. It helps here to have a visual EQ so you can see what needs to change. Once those frequencies are gone, you can up the volume a bit because now those other frequencies aren't using up any of the amplitude on your waveform.
I generally render my tracks at no more than +1.0 dB, and no less than -1.0 dB max. Then I pull it into Audacity, use Hard Clipper to remove 2 or 3 dB from the top, and then use amplify to bring the track back up to 0.0 dB. This evens out the loudness throughout the track while making it as loud as possible with what I've got. I've found that slightly clipping (~+1.5 dB) is ok sometimes (usually only in short, sharp hits and such), but things like SoundCloud make it sound like crap anyway.